Madera y corteza de algunas Rubiaceae en México: similitud estructural

Abstract

Wood and bark anatomy of 42 species of Rubiaceae from 8 tribes were studied with the aim to assess whether the anatomical characters allow separation of species belonging to the different genera in Mexico and whether characters are related to the environment where they live or their habit. Two groups resulted in the phenogram, corresponding to wood type I and II sensu Koek-Noorman. Not all species of Bouvardia and Psychotria grouped in their respective genera and Notopleura anomothyrsa is different from the other species having fibertracheids and scalariform intervascular pits. The Arachnothryx, Chione, Exostema, Hintonia and Randia group with wood type I presents rhytidome, bands of sclereids and 3 types of crystals in the phloem, and are trees or shrubs of the seasonal dry forest and the cloud forest. The group with wood type II has a single periderm, endodermis, groups of fibers/sclereids and raphides in the phloem, and are shrubs of the tropical rainforest, seasonal dry forest, cloud forest, and pine-oak forest. Growth rings in these species may be associated with phenology and habitat conditions, but vessel diameter and density appear to have a strong phylogenetic signal.